load plugins from multiple paths

[milahu]

what

radare2 should load plugins from multiple paths

R2_LIBR_PLUGIN_PATH=/path/a:/path/b:/path/c r2

similar to MOZ_PLUGIN_PATH, QT_PLUGIN_PATH, QTWEBKIT_PLUGIN_PATH, ...

why

make radare plugins play nice with package managers like nix

downstream issues:

• Radare2 with Ghidra NixOS/nixpkgs#86448 (comment)
• Linux build errors v5.7.8 r2ghidra#100 (comment) (packaging for guix)

current situation

(i hope that im wrong but ...)

currently, plugins are loaded from *one* path

either from R2_LIBR_PLUGINS (defined on compiletime)
or from getenv("R2_LIBR_PLUGINS") (defined on runtime)

radare2/doc/plugins.md

Lines 1 to 13 in 510ddab

	LIBR PLUGINS
	============
	Plugins must be configured using the root ./configure-plugins script.
	Libraries can be compiled:
	- as shared libraries (so, dylib, dll) (DEFAULT)
	- as static libraries (a, lib, ..)
	./configure-plugins --enable-shared --enable-dynamic
	R2_LIBR_PLUGINS environment variable is honored as another search path for plugins

radare2/libr/include/r_lib.h

Line 22 in b8e6b52

#define R_LIB_ENV "R2_LIBR_PLUGINS"

radare2/libr/core/libs.c

Lines 76 to 78 in 1100e12

	char *p = r_sys_getenv (R_LIB_ENV);
	if (p && *p) {
	r_lib_opendir (core->lib, p);

radare2/libr/util/lib.c

Line 357 in abb7a7c

R_API bool r_lib_opendir(RLib *lib, const char *path) {

R_API bool r_lib_opendir(RLib *lib, const char *path) {
// ...
#ifdef R2_LIBR_PLUGINS
	if (!path) {
		path = R2_LIBR_PLUGINS;
	}
#endif

challenges

• deduplicate plugins Fix #16281 - Do not load system-wide plugins twice ##core #16431
• check if plugin version is compatible
• expose this function to plugins, so plugins can find other plugins

workaround

use the R2_LIBR_PLUGINS env variable and symlink multiple plugins into one folder

related

radare2/libr/include/r_userconf.h.acr

Line 66 in abb7a7c

#define R2_PLUGINS "lib/radare2/" R2_VERSION

will be replaced by #20545

#define R2_VERSION_ABI "@R2_VERSION_MAJOR@.@[email protected]"

#define R2_PLUGINS "lib/radare2/" R2_VERSION_ABI
#define R2_EXTRAS "lib/radare2-extras/" R2_VERSION_ABI
#define R2_BINDINGS "lib/radare2-bindings/" R2_VERSION_ABI

... ideally also support multiple paths for extras and bindings

[trufae]

Please submit the patch as a pullrequest its better place to discuss code changes than issues

[milahu]

sorry, this is low priority because has workaround

[trufae]

ill take a look when i have some spare time this or next week, thanks for reporting!

[trufae]

you can use the R2_LIBR_PLUGINS env var already but its just one string with the absolute path, i can split that with colons to support multoiple paths. but libr/core/libs.c already handles this env var